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Discussion Intel current and future Lakes & Rapids thread

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JoeRambo

Golden Member
Jun 13, 2013
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On Windows 10 many programs are using the small cores and games could drop by about 50 fps, Windows 11 is a must have. DDR4-3600 Gear1 is possible and (unsurprisingly) best choice for high fps gaming. DDR5 is Gear2 by default, Gear4 is for 10000+ speeds. 40% higher latency on DDR5, might need 8000+ speeds to compensate. The best ADL-S is definitely better than 5950X for gaming. Good heat dissipation.

Yeah, leaks are flowing in, with each passing day. Pretty much expected stuff, maybe Intel will pull a wonder uCode for DDR5, cause right now things are not looking good for it. Very interesting situation for well-informed enthusiasts: DDR5 comes with penalties, while there are no true higher end Z690 motherboards with DDR4.
Mobo makers will keep on selling stuff, but they will be missing at least $150 from me.
 
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LightningZ71

Senior member
Mar 10, 2017
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So, the answer for Win 10 is to either disable the E cores, or, get a 12600T or lower that doesn't have E cores to begin with. Makes sense on some level, though, Win10 was supposed to understand Hybrid designs from its use on the Arm and earlier Intel Hybrid design.
 

Carfax83

Diamond Member
Nov 1, 2010
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DDR5 is Gear2 by default, Gear4 is for 10000+ speeds. 40% higher latency on DDR5, might need 8000+ speeds to compensate.
I don't get it, why does DDR5 have such higher latencies? It's like the designers don't care about trying to minimize latency, and all they care about is bandwidth. :confused:

I expect initial DDR5 batches to have higher latencies of course, but it seems the issue is endemic rather and won't be ameliorated over time like previous releases. I know that bandwidth is a much bigger problem in commercial and HPC sectors, but I didn't expect the memory consortiums to go all in to this extent.

It seems we will need 10ghz plus DDR5 to even come close to matching the latencies we can get now with high frequency DDR4. I have a thought that Alder Lake will be similar to Haswell, in the sense that the memory controller will be kind of half assed for DDR5 performance much like how Haswell was with DDR4. Raptor Lake will likely have a much better memory controller for DDR5 than Alder Lake, like Broadwell did for DDR4.
 

Doug S

Senior member
Feb 8, 2020
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If you double the clock rate of memory you double the latency when measured in memory clock cycles - but it remains the same in nanoseconds which is what matters for the CPU.

Initial batches of a new memory technology are always targeted at the early adopters with deep pockets. Sorry gamers, that's not you! They are targeted at servers and HPC, so they have pretty conservative timings, and they have no reason to bin them right now because the HPC and server customers don't buy overclocked and aggressively timed DRAM like gamers do. That's why DDR5 looks worse than DDR4 right now - because you are comparing conservatively timed DDR5 with the heavily binned, aggressively timed and overclocked DDR4 you can buy.

Once DDR5 production is high enough for them to satisfy the HPC/server market and start thinking about binning they'll find some chips that test out to operate at higher clock rates and lower latencies and sell them in overclocked and aggressively timed DIMMs to gamers. Same thing happened with the DDR4 transition, and the DDR3 transition, and ...
 

dullard

Elite Member
May 21, 2001
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If you double the clock rate of memory you double the latency when measured in memory clock cycles - but it remains the same in nanoseconds which is what matters for the CPU.

Initial batches of a new memory technology are always targeted at the early adopters with deep pockets. Sorry gamers, that's not you! They are targeted at servers and HPC, so they have pretty conservative timings, and they have no reason to bin them right now because the HPC and server customers don't buy overclocked and aggressively timed DRAM like gamers do. That's why DDR5 looks worse than DDR4 right now - because you are comparing conservatively timed DDR5 with the heavily binned, aggressively timed and overclocked DDR4 you can buy.

Once DDR5 production is high enough for them to satisfy the HPC/server market and start thinking about binning they'll find some chips that test out to operate at higher clock rates and lower latencies and sell them in overclocked and aggressively timed DIMMs to gamers. Same thing happened with the DDR4 transition, and the DDR3 transition, and ...
Exactly. For example, Samsung's 768 GB (per stick) DDR5 memory is just not aimed for gamers.
 

jpiniero

Lifer
Oct 1, 2010
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Once DDR5 production is high enough for them to satisfy the HPC/server market and start thinking about binning they'll find some chips that test out to operate at higher clock rates and lower latencies and sell them in overclocked and aggressively timed DIMMs to gamers. Same thing happened with the DDR4 transition, and the DDR3 transition, and ...
There will be overclocked DDR5 available. It still won't have the same effective latency as 4800 CL19. This ram has an XMP profile of 6200 CL38.

 
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Carfax83

Diamond Member
Nov 1, 2010
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If you double the clock rate of memory you double the latency when measured in memory clock cycles - but it remains the same in nanoseconds which is what matters for the CPU.
Then why have all the memory related benchmarks we've seen so far (measured in nanoseconds) been FAR higher?

Even the additional factors like gear ratios and unoptimized timings don't explain such a massive gain in latency if you ask me.

And the Chinese FAQ mikk posted states that DDR5's latencies are about 40% higher than DDR4 at the same frequency and timings when tested. That's not a small difference at all.
 

LightningZ71

Senior member
Mar 10, 2017
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The generalized explanation is that, to reach the MUCH higher clocks that the DDR5 spec allows over DDR4, certain base latencies had to be greatly expanded. It takes time to setup the communication channels for each transfer, and the higher you push the clocks, the more rigorous the techniques must be to ensure that the bus is stable for the desired frequency. That's HEAVILY simplified of course, but, that's the gist of it.
 

Doug S

Senior member
Feb 8, 2020
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Then why have all the memory related benchmarks we've seen so far (measured in nanoseconds) been FAR higher?
I told you why. Because it isn't being binned to cherry pick the best chips to make DIMMs capable of minimal latency.

I'm not sure what process DRAM makers are using these days, but they might be using a newer process to make DDR5 chips which isn't as mature as the process being using to make most DDR4 chips.

Perhaps the internal ECC calculations might add a bit of latency, so maybe DDR5 never gets quite as fast as DDR4 even when it is being binned within an inch of its life on a mature process like DDR4. If so that would be maybe 5-10% at most though, not 40%.
 
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mikk

Diamond Member
May 15, 2012
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Then why have all the memory related benchmarks we've seen so far (measured in nanoseconds) been FAR higher?

Even the additional factors like gear ratios and unoptimized timings don't explain such a massive gain in latency if you ask me.

And the Chinese FAQ mikk posted states that DDR5's latencies are about 40% higher than DDR4 at the same frequency and timings when tested. That's not a small difference at all.
Most leaks might have used DDR5-4800 CL40 which is much worse than DDR4-3200 CL15 when it comes to latency. And Gear2 doesn't help.
 

moinmoin

Platinum Member
Jun 1, 2017
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LOL! You think gamers are responsible for that? That's the crypto miners and AI people's doing, not the gamers.
No, I didn't write anything about responsibility or putting blame on anybody. Just when I read the description of "early adopters with deep pockets" I personally first think of gamers. The more expensive consumer PCs even way before any of the crypto and AI stuff even existed were often focused on gamers. They make an easy target for more expensive newly introduced consumer products.
 

Doug S

Senior member
Feb 8, 2020
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No, I didn't write anything about responsibility or putting blame on anybody. Just when I read the description of "early adopters with deep pockets" I personally first think of gamers. The more expensive consumer PCs even way before any of the crypto and AI stuff even existed were often focused on gamers. They make an easy target for more expensive newly introduced consumer products.
The enterprise world has always been first to move on new memory and storage standards. First to a new DDRx standard, first to larger capacity hard drives, adopted SSDs years before they appeared in the consumer world, etc.
 

mikk

Diamond Member
May 15, 2012
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Is Gear1 possible with DDR5?

Apparently only gear 2 and gear 4. You can read from the google translation.


DDR4 can be Gear 1, DDR5 basically can only be used for Gear 2 and Gear 4. At present, if DDR4 is used under Gear 1, it is a level of 3600MHz. The Uncore voltage can be increased to 3866, so the DDR4 part is hardly improved. DDR5 is Gear 2 by default, so if there is any improvement, you need to see the 8000+ note. As for Gear 4, that’s what 10GHz+ memory should be concerned about.
 
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uzzi38

Golden Member
Oct 16, 2019
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As of right now you can set it, but YMMV basically. The default setting is just straight to Gear2.
 

Carfax83

Diamond Member
Nov 1, 2010
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I'm withholding judgment till the reviews drop, but as I said before, I wouldn't be surprised if Alder Lake's memory controller will be unpolished and half assed for DDR5 performance, with Raptor Lake being much superior in that regard.

When Haswell-E made its debut with DDR4, it had a write performance bug that was fixed with Broadwell-E. Also, Broadwell-E's memory controller was able to hit higher memory clocks with less voltage, proving that it had a much more capable memory controller for DDR4 than Haswell-E.
 

mikk

Diamond Member
May 15, 2012
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ADL-S must be a nightmare for reviewer with all the possibilities. Windows 10, windows 11, DDR4, DDR5, big cores, small cores. I guess most will go with DDR5 and Windows 11. Hopefully some will do a DDR4 versus DDR5 comparison.
 

clemsyn

Senior member
Aug 21, 2005
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I'd say the real nonsense will start when the reviews drop.
Agree! Can't wait for anandtech for reviews. I don't think Pat (CEO) has anything to do with the development of Alderlake, right? If so, how soon can we find a release with his work?
 

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